The present invention relates to pharmaceutical compositions containing, as active ingredient, at least one compound of formula: 
or one of its pharmaceutically acceptable salts, to the novel derivatives of formula (I), to their pharmaceutically acceptable salts and to their preparation as well as to their use in treating various disorders of the nervous system.
R3 represent phenyl radicals, R1 represents a radical xe2x80x94N(R5)xe2x80x94Yxe2x80x94R6, Y is SO2, R5 represents a methyl radical and R6 represents a phenyl radical is described as a synthesis intermediate in Patent WO 99/01451. The other compounds and their pharmaceutically acceptable salts are novel and as such form parts of the invention.
In formula (I)
R1 represents a radical xe2x80x94NHCOR4 or xe2x80x94N(R5)xe2x80x94Yxe2x80x94R6,
Y is CO or SO2,
R2 and R3, which are identical or different, represent either an aromatic selected from phenyl, naphthyl and indenyl, these aromatics being unsubstituted or substituted with one or more halogen atoms or alkyl, alkoxy, formyl, hydroxyl, trifluoromethyl, trifluoro-methoxy, xe2x80x94CO-alk, cyano, xe2x80x94COOH, xe2x80x94COOalk, xe2x80x94CONR7R8, xe2x80x94COxe2x80x94NHxe2x80x94NR9R10, alkylsulfanyl, alkylsulfinyl, alkyl-sulfonyl, alkylsulfanylalkyl, alkylsulfinylalkyl, alkylsulfonylalkyl, hydroxyalkyl or -alk-NR7R8 radicals; or a heteroaromatic selected from benzofuryl, benzothiazolyl, benzothienyl, benzoxazolyl, chromanyl, 2,3-dihydrobenzofuryl, 2,3-dihydrobenzothienyl, pyrimidinyl, furyl, imidazolyl, isochromanyl, isoquinolyl, pyrrolyl, pyridyl, quinolyl, 1,2,3,4-tetrahydro-isoquinolyl, thiazolyl and thienyl rings, it being possible for these heteroaromatics to be unsubstituted or substituted with a halogen atom or an alkyl, alkoxy, hydroxyl, trifluoromethyl, trifluoromethoxy, cyano, xe2x80x94COOH, xe2x80x94COOalk, xe2x80x94COxe2x80x94NHxe2x80x94NR9R10, xe2x80x94CONR7R8, -alk-NR9R10, alkylsulfanyl, alkylsulfinyl, alkylsulfonyl, alkylsulfanylalkyl, alkylsulfinylalkyl, alkylsulfonylalkyl or hydroxyalkyl radical,
R4 represents a radical -alk-SO2xe2x80x94R11, -alk-SO2xe2x80x94CHxe2x95x90CHxe2x80x94R11, Het substituted with xe2x80x94SO2xe2x80x94R11 or phenyl substituted with xe2x80x94SO2xe2x80x94R11 or -alk-SO2xe2x80x94R11,
R5 represents a hydrogen atom or an alkyl radical,
R6 represents a phenylalkyl, Het or Ar radical,
R7 and R8, which are identical or different, represent a hydrogen atom or an alkyl radical or alternatively R7 and R8 together form with the nitrogen atom to which they are attached a 3- to 10-membered saturated mono- or bicyclic heterocycle, optionally containing another heteroatom selected from oxygen, sulfur and nitrogen and being optionally substituted with one or more alkyl radicals,
R9 and R10, which are identical or different, represent a hydrogen atom or an alkyl, xe2x80x94COOalk, cycloalkyl, alkylcycloalkyl, -alk-O-alk or hydroxyalkyl radical or alternatively R9 and R10 together form with the nitrogen atom to which they are attached a 3- to 10-membered saturated or unsaturated mono- or bicyclic heterocycle, optionally containing another heteroatom selected from oxygen, sulfur and nitrogen and being optionally substituted with one or more alkyl, xe2x80x94COalk, xe2x80x94COOalk, xe2x80x94COxe2x80x94NHalk, xe2x80x94CSxe2x80x94NHalk, oxo, hydroxyalkyl, -alk-O-alk or xe2x80x94COxe2x80x94NH2 radicals,
R11 represents an alkyl, Ar or Het radical,
Ar represents a phenyl, naphthyl or indenyl radical, these radicals being optionally substituted with one or more halogen atoms or alkyl, alkoxy, cyano, xe2x80x94CO-alk, xe2x80x94COOH, xe2x80x94COOalk, xe2x80x94CONR12R13, xe2x80x94COxe2x80x94NHxe2x80x94NR14R15, alkylsulfanyl, alkylsulfinyl, alkylsulfonyl, -alk-NR14R15, xe2x80x94NR14R15, alkylthioalkyl, formyl, hydroxyl, hydroxyalkyl, Het, xe2x80x94O-alk-NH-cycloalkyl, OCF3, CF3, xe2x80x94NHxe2x80x94CO-alk, xe2x80x94SO2NH2, xe2x80x94NHxe2x80x94COCH3, xe2x80x94NHxe2x80x94COOalk or Het radicals, or alternatively, on 2 adjacent carbon atoms, with a dioxymethylene,
Het represents a 3- to 10-membered unsaturated or saturated mono- or bicyclic heterocycle containing one or more heteroatoms selected from oxygen, sulfur and nitrogen optionally substituted with one or more halogen atoms or alkyl, alkoxy, vinyl, alkoxycarbonyl, oxo, hydroxyl, OCF3 or CF3 radicals, the nitrogen-containing heterocycles being optionally in their N-oxidized form,
R12 and R13, which are identical or different, represent a hydrogen atom or an alkyl radical or alternatively R12 and R13 together form with the nitrogen atom to which they are attached a 3- to 10-membered saturated mono- or bicyclic heterocycle, optionally containing another heteroatom selected from oxygen, sulfur and nitrogen and being optionally substituted with one or more alkyl radicals,
R14 and R15, which are identical or different, represent a hydrogen atom or an alkyl, xe2x80x94COOalk, cycloalkyl, alkylcycloalkyl, -alk-O-alk or hydroxyalkyl radical or alternatively R14 and R15 together form with the nitrogen atom to which they are attached a 3- to 10-membered saturated or unsaturated mono- or bicyclic heterocycle, optionally containing another heteroatom selected from oxygen, sulfur and nitrogen and being optionally substituted with one or more alkyl, xe2x80x94COalk, xe2x80x94COOalk, xe2x80x94COxe2x80x94NHalk, xe2x80x94CSxe2x80x94NHalk, oxo, hydroxyalkyl, -alk-O-alk or xe2x80x94COxe2x80x94NH2 radicals,
alk represents an alkyl or alkylene radical.
In the preceding definitions and in those which follow, unless otherwise stated, the alkyl and alkylene radicals and portions and the alkoxy radicals and portions are in the form of a straight or branched chain and contain 1 to 6 carbon atoms and the cycloalkyl radicals contain 3 to 10 carbon atoms.
Among the alkyl radicals, there may be mentioned the methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, iso-butyl, tert-butyl, pentyl and hexyl radicals. Among the alkoxy radicals, there may be mentioned the methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, iso-butoxy, sec-butoxy, tert-butoxy and pentyloxy radicals.
Among the cycloalkyl radicals, there may be mentioned the cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl radicals.
The term halogen comprises chlorine, fluorine, bromine and iodine.
Among the heterocycles represented by Het, the following heterocycles may be mentioned: benzimidazole, benzoxazole, benzothiazole, benzothiophene, cinnoline, thiophene, quinazoline, quinoxaline, quinoline, pyrazole, pyrrole, pyridine, imidazole, indole, isoquinoline, pyrimidine, thiazole, thiadiazole, piperidine, piperazine, pyrrolidine, triazole, furan, tetrahydroisoquinoline, tetrahydroquinoline, these heterocycles being optionally substituted with one or more halogen atoms or alkyl, alkoxy, vinyl, alkoxycarbonyl, oxo, hydroxyl, OCF3 or CF3 radicals.
The compounds of formula (I) may be provided in the form of enantiomers and of diastereoisomers. These optical isomers and mixtures thereof also form part of the invention.
Preferably, the compounds of formula (I) are those for which
R1 represents a radical xe2x80x94N(R5)xe2x80x94Yxe2x80x94R6,
Y is SO2,
R2 represents either a phenyl which is unsubstituted or substituted with one or more halogen atoms or alkyl, alkoxy, trifluoromethyl, trifluoromethoxy, cyano, xe2x80x94CONR7R8, hydroxyalkyl or -alk-NR7R8 radicals; or a heteroaromatic selected from the pyridyl, pyrimidyl, thiazolyl and thienyl rings, it being possible for these heteroaromatics to be unsubstituted or substituted with a halogen atom or an alkyl, alkoxy, hydroxyl, trifluoromethyl, trifluoromethoxy, xe2x80x94CONR7R8, -alk-NR9R10, alkylsulfanyl, alkylsulfinyl, alkylsulfonyl or hydroxyalkyl radical,
R3 represents either a phenyl which is unsubstituted or substituted with one or more halogen atoms or alkyl, alkoxy, trifluoromethyl, trifluoromethoxy, cyano, xe2x80x94CONR7R8, hydroxyalkyl or -alk-NR7R8 radicals; or a heteroaromatic selected from the pyridyl, pyrimidyl, thiazolyl and thienyl rings, it being possible for these heteroaromatics to be unsubstituted or substituted with a halogen atom or an alkyl, alkoxy, hydroxyl, trifluoromethyl, trifluoromethoxy, xe2x80x94CONR7R8, -alk-NR9R10, alkylsulfanyl, alkylsulfinyl, alkylsulfonyl or hydroxyalkyl radical,
R5 represents a hydrogen atom or an alkyl radical,
R6 represents a naphthyl, phenylalkyl, Het or phenyl radical optionally substituted with one or more halogen atoms or alkyl, alkoxy, cyano, xe2x80x94CO-alk, COOalk, xe2x80x94CONR12R13, -alk-NR14R15, xe2x80x94NR14R15, hydroxyl, hydroxyalkyl, Het, OCF3, CF3, xe2x80x94NHxe2x80x94CO-alk, xe2x80x94SO2NH2 or xe2x80x94NHxe2x80x94COOalk radicals, or alternatively, on 2 adjacent carbon atoms, with dioxymethylene,
R7 and R8, which are identical or different, represent a hydrogen atom or an alkyl radical or alternatively R7 and R8 together form with the nitrogen atom to which they are attached a 3- to 10-membered saturated mono- or bicyclic heterocycle, optionally containing another heteroatom selected from oxygen, sulfur and nitrogen and being optionally substituted with one or more alkyl radicals,
R9 and R10, which are identical or different, represent a hydrogen atom or an alkyl, cycloalkyl, alkylcycloalkyl or hydroxyalkyl radical or alternatively R9 and R10 together form with the nitrogen atom to which they are attached a 3- to 10-membered saturated or unsaturated mono- or bicyclic heterocycle, optionally containing another heteroatom selected from oxygen, sulfur and nitrogen and being optionally substituted with one or more alkyl, oxo or xe2x80x94COxe2x80x94NH2 radicals,
R12 and R13, which are identical or different, represent a hydrogen atom or an alkyl radical or alternatively R12 and R13 together form with the nitrogen atom to which they are attached a 3- to 10-membered saturated mono- or bicyclic heterocycle, optionally containing another heteroatom selected from oxygen, sulfur and nitrogen and being optionally substituted with one or more alkyl radicals,
R14 and R15, which are identical or different, represent a hydrogen atom or an alkyl, cycloalkyl, alkylcycloalkyl or hydroxyalkyl radical or alternatively R14 and R15 together form with the nitrogen atom to which they are attached a 3- to 10-membered saturated or unsaturated mono- or bicyclic heterocycle, optionally containing another heteroatom selected from oxygen, sulfur and nitrogen and being optionally substituted with one or more alkyl, oxo, hydroxyalkyl or xe2x80x94COxe2x80x94NH2 radicals,
Het represents a 3- to 10-membered unsaturated or saturated mono- or bicyclic heterocycle containing one or more heteroatoms selected from oxygen, sulfur and nitrogen optionally substituted with one or more halogen atoms or alkyl, alkoxy, vinyl, alkoxycarbonyl, oxo or hydroxyl radicals, the nitrogen-containing heterocycles being optionally in their N-oxidized form and, preferably, Het represents a heterocycle selected from the following heterocycles: benzimidazole, benzoxazole, benzothiazole, benzothiophene, thiophene, quinazoline, quinoxaline, quinoline, pyrrole, pyridine, imidazole, indole, isoquinoline, pyrimidine, thiazole, thiadiazole, furan, tetrahydroisoquinoline and tetrahydroquinoline, these heterocycles being optionally substituted with one or more halogen atoms or alkyl, alkoxy, vinyl, oxo, hydroxyl, OCF3 or CF3 radicals.
Still more preferably, the compounds of formula (I) are selected from the following compounds:
R1 represents a radical xe2x80x94N(R5)xe2x80x94Yxe2x80x94R6,
Y is SO2,
R2 represents either a phenyl which is unsubstituted or substituted with one or more halogen atoms or alkyl, alkoxy, trifluoromethyl, trifluoromethoxy or hydroxyalkyl radicals; or a heteroaromatic selected from pyridyl and pyrimidyl rings, it being possible for these heteroaromatics to be unsubstituted or substituted with a halogen atom or an alkyl, alkoxy, hydroxyl, trifluoromethyl or trifluoromethoxy radical,
R3 represents either a phenyl which is unsubstituted or substituted with one or more halogen atoms or alkyl, alkoxy, trifluoromethyl, trifluoromethoxy or hydroxyalkyl radicals; or a heteroaromatic selected from pyridyl and pyrimidyl rings, it being possible for these heteroaromatics to be unsubstituted or substituted with a halogen atom or an alkyl, alkoxy, hydroxyl, trifluoromethyl or trifluoromethoxy radical,
R5 represents a hydrogen atom or an alkyl radical,
R6 represents a naphthyl, phenylalkyl, Het or phenyl radical optionally substituted with one or more halogen atoms or alkyl, alkoxy, xe2x80x94NR14R15, hydroxyl, hydroxyalkyl, OCF3, CF3 or xe2x80x94SO2NH2 radicals, or alternatively, on 2 adjacent carbon atoms, with dioxymethylene,
R14 and R15, which are identical or different, represent a hydrogen atom or an alkyl, cycloalkyl, alkylcycloalkyl or hydroxyalkyl radical or alternatively R14 and R15 together form with the nitrogen atom to which they are attached a 3- to 10-membered saturated or unsaturated mono- or bicyclic heterocycle, optionally containing another heteroatom selected from oxygen, sulfur and nitrogen and being optionally substituted with one or more alkyl, oxo, hydroxyalkyl or xe2x80x94COxe2x80x94NH2 radicals,
Het represents a 3- to 10-membered unsaturated or saturated mono- or bicyclic heterocycle containing one or more heteroatoms selected from oxygen, sulfur and nitrogen optionally substituted with one or more halogen atoms or alkyl, alkoxy, vinyl, alkoxycarbonyl, oxo or hydroxyl radicals, the nitrogen-containing heterocycles being optionally in their N-oxidized form and, preferably, Het represents a heterocycle selected from the following heterocycles: benzimidazole, benzoxazole, benzothiazole, benzothiophene, thiophene, quinoline, pyrrole, pyridine, pyrimidine, thiazole, thiadiazole, furan, tetrahydroisoquinoline and tetrahydroquinoline, these heterocycles being optionally substituted with one or more halogen atoms or alkyl, alkoxy, vinyl, oxo, hydroxyl, OCF3 or CF3 radicals.
The compounds of formula (I) for which R1 represents a radical xe2x80x94NHCOR4 may be prepared according to the following reaction scheme: 
In these formulae, R2, R3 and R4 have the same meanings as in formula (I).
Step a is generally carried out in an inert solvent such as tetrahydrofuran, dioxane, a chlorinated solvent (for example dichloromethane or chloroform), at a temperature of between 15 and 30xc2x0 C., in the presence of a base such as a trialkylamine (for example triethylamine or dipropylethylamine) or in pyridine, at a temperature of between 0 and 30xc2x0 C.
Step b is preferably carried out in methanol, in an autoclave, at a temperature of between 50 and 70xc2x0 C.
Step c is generally carried out in the presence of a condensing agent used in peptide chemistry, such as a carbodiimide (for example 1-(3-dimethylamiopropyl)-3-ethylcarbodiimide or N,Nxe2x80x2-dicyclohexylcarbodiimide) or N,Nxe2x80x2carbonyl-diimidazole, in an inert solvent such as an ether (for example tetrahydrofuran or dioxane), an amide (dimethylformamide) or a chlorinated solvent (for example methylene chloride, 1,2-dichloroethane or chloroform) at a temperature of between 0xc2x0 C. and the boiling point of the reaction mixture. It is also possible to use a reactive derivative of the acid such as an acid chloride, optionally in the presence of an acid acceptor such as a nitrogen-containing organic base (for example trialkylamine, pyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene or 1,5-diazabicyclo[4.3.0]-non-5-ene), in a solvent as cited above, or a mixture of these solvents, at a temperature of between 0xc2x0 C. and the boiling point of the reaction mixture.
The derivatives R4COOH are commercially available or may be obtained according to the methods described in R. C. LAROCK, Comprehensive Organic Transformations, VCH editor.
The azetidinols of formula 1 may be obtained by application or adaptation of the methods described by KATRITZKY A. R. et al., J. Heterocycl. Chem., 271 (1994) or DAVE P. R., J. Org. Chem., 61, 5453 (1996) and in the examples. The procedure is generally carried out according to the following reaction scheme: 
in these formulae, R2 and R3 have the same meanings as in formula (I) and Hal represents a chlorine or bromine atom.
In step A, the procedure is preferably carried out in an inert solvent such as a 1-4C aliphatic alcohol (for example ethanol or methanol), optionally in the presence of an alkali metal hydroxide, at the boiling point of the reaction medium.
In step B, the reduction is generally carried out by means of lithium aluminum hydride, in tetrahydrofuran at the boiling point of the reaction medium.
In step C, the procedure is preferably carried out in an inert solvent such as a 1-4C aliphatic alcohol (for example ethanol or methanol), in the presence of sodium hydrogen carbonate, at a temperature of between 20xc2x0 C. and the boiling point of the reaction medium.
In step D, the procedure is carried out according to the method described by GRISAR M. et al. in J. Med. Chem., 885 (1973). The magnesium compound of the brominated derivative is formed and then the nitrile is caused to react, in an ether such as ethyl ether, at a temperature of between 0xc2x0 C. and the boiling point of the reaction medium. After hydrolysis with an alcohol, the intermediate imine is reduced in situ with sodium borohydride at a temperature of between 0xc2x0 C. and the boiling point of the reaction medium.
The derivatives R2xe2x80x94COxe2x80x94R3 are commercially available or may be obtained by application or adaptation of the methods described by KUNDER N. G. et al. J. Chem. Soc. Perkin Trans 1, 2815 (1997); MORENO-MARRAS M., Eur. J. Med. Chem., 23 (5) 477 (1988); SKINNER et al., J. Med. Chem., 14 (6) 546 (1971); HURN N. K., Tet. Lett., 36 (52) 9453 (1995); MEDICI A. et al., Tet. Lett., 24 (28) 2901 (1983); RIECKE R. D. et al., J. Org. Chem., 62 (20) 6921 (1997); KNABE J. et al., Arch. Pharm., 306 (9) 648 (1973); CONSONNI R. et al., J. Chem. Soc. Perkin Trans 1, 1809 (1996); FR-96-2481 and JP-94-261393.
The derivatives R3Br are commercially available or may be obtained by application or adaptation of the methods described by BRANDSMA L. et al., Synth. Comm., 20 (11) 1697 and 3153 (1990); LEMAIRE M. et al., Synth. Comm., 24 (1) 95 (1994); GODA H. et al., Synthesis, 9 849 (1992); BAEUERLE P. et al., J. Chem. Soc. Perkin Trans 2, 489 (1993).
The derivatives R2CN are commercially available or may be obtained by application or adaptation of the methods described by BOUYSSOU P. et al., J. Het. Chem., 29 (4) 895 (1992); SUZUKI N. et al., J. Chem. Soc. Chem. Comm., 1523 (1984); MARBURG S. et al., J. Het. Chem., 17 1333 (1980); PERCEC V. et al., J. Org. Chem., 60 (21) 6895 (1995).
The compounds of formula (I) for which R1 represents a radical xe2x80x94N(R5)xe2x80x94Yxe2x80x94R6 may be prepared according to the following reaction scheme: 
in these formulae, Y, R2, R3 and R6 have the same meanings as in formula (I), Hal represents a halogen atom and, preferably, an iodine, chlorine or bromine atom.
Step a is generally carried out in an inert solvent such as tetrahydrofuran, dioxane or a chlorinated solvent (for example dichloromethane or chloroform), in the presence of an amine such as a trialkylamine (for example triethylamine), at a temperature of between 5xc2x0 C. and 20xc2x0 C.
Step b is generally carried out in an inert solvent such as tetrahydrofuran, in the presence of sodium hydride, at a temperature of 0xc2x0 C. and the boiling point of the reaction medium.
The Hal-SO2R6 derivatives are commercially available or may be obtained by halogenation of the corresponding sulfonic acids, in particular in situ in the presence of chlorosulfonyl isocyanate and alcohol, in a halogenated solvent (for example dichloromethane or chloroform).
The Hal-COxe2x80x94R6 derivatives are commercially available or may be prepared according to the methods described in R. C. LAROCK, Comprehensive Organic Transformations, VCH editor.
The compounds of formula (I) may also be prepared according to the following reaction scheme: 
In these formulae, R1, R2 and R3 have the same meanings as in formula (I) and Ph represents a phenyl.
Step a is generally carried out in an alcohol such as methanol, in the presence of sodium borohydride, at a temperature in the region of 20xc2x0 C.
In step b, the magnesium compound of the brominated derivative is prepared and it is caused to react, in an inert solvent such as ethyl ether or tetrahydrofuran, at a temperature of between 0xc2x0 C. and the boiling point of the reaction medium.
Step c is carried out by means of a halogenating agent such as hydrobromic acid, thionyl bromide, thionyl chloride, a mixture of triphenylphosphine and carbon tetrabromide or tetrachloride, in acetic acid or an inert solvent such as dichloromethane, chloroform, carbon tetrachloride or toluene, at a temperature of between 0xc2x0 C. and the boiling point of the reaction medium.
Step d is carried out by means of hydrogen, in the presence of palladized charcoal, in an alcohol such as methanol, at a temperature in the region of 20xc2x0 C.
Step e is carried out in an inert solvent such as acetonitrile, in the presence of an alkali metal carbonate (for example potassium carbonate) and potassium iodide, at a temperature of between 20xc2x0 C. and the boiling point of the reaction medium.
The derivatives R3Br and the derivatives R2xe2x80x94CHO are commercially available or may be obtained according to the methods described for example by R. C. LAROCK, Comprehensive Organic Transformations, VCH editor.
The compounds of formula (I) for which R1 represents a radical xe2x80x94N(R5)xe2x80x94Yxe2x80x94R6 in which R6 is a phenyl radical substituted with a hydroxyl radical may also be prepared by hydrolysis of a corresponding compound of formula (I) for which R1 represents a radical xe2x80x94N(R5)xe2x80x94Yxe2x80x94R6 in which R6 is a phenyl radical substituted with an alkoxy radical.
This hydrolysis is generally carried out in an inert solvent such as a chlorinated solvent (for example dichloromethane or chloroform), by means of boron tribromide, at a temperature in the region of 20xc2x0 C.
The compounds of formula (I) for which R1 represents a radical xe2x80x94N(R5)xe2x80x94Yxe2x80x94R6 in which R6 is a phenyl radical substituted with a hydroxy(1C)alkyl radical may also be prepared by the action of diisobutylaluminum hydride on a corresponding compound of formula (I) for which R1 represents a radical xe2x80x94N(R5)xe2x80x94Yxe2x80x94R6 in which R6 is a phenyl radical substituted with an alkoxycarbonyl radical.
This reaction is generally carried out in an inert solvent such as toluene, by means of diisopropyl-aluminum hydride, at a temperature of between xe2x88x9250xc2x0 C. and 25xc2x0 C.
The compounds of formula (I) for which R1 represents a radical xe2x80x94N(R5)xe2x80x94Yxe2x80x94R6 in which R6 is a phenyl radical substituted with a 1-pyrrolidinyl radical may also be prepared by the action of pyrrolidine and of a corresponding compound of formula (I) for which R1 represents a radical xe2x80x94N(R5)xe2x80x94Yxe2x80x94R6 in which R6 is a phenyl radical substituted with a fluorine atom.
This reaction is preferably carried out in an inert solvent such as dimethyl sulfoxide, at a temperature of 90xc2x0 C.
It is understood for persons skilled in the art that, to carry out the processes according to the invention which are described above, it may be necessary to introduce groups protecting amino, hydroxyl and carboxyl functions in order to avoid side reactions. These groups are those which allow removal without affecting the rest of the molecule. As examples of groups protecting the amino function, there may be mentioned tert-butyl or methyl carbamates which may be regenerated using iodotrimethylsilane or allyl using palladium catalysts. As examples of groups protecting the hydroxyl function, there may be mentioned triethylsilyl and tert-butyldimethylsilyl which may be regenerated using tetrabutylammonium fluoride or alternatively asymmetric acetals (methoxymethyl or tetrahydropyranyl for example) with regeneration using hydrochloric acid. As groups protecting carboxyl functions, there may be mentioned esters (allyl or benzyl for example), oxazoles and 2-alkyl-1,3-oxazolines. Other protecting groups which can be used are described by GREENE T. W. et al., Protecting Groups in Organic Synthesis, second edition, 1991, John Wiley and Sons.
The compounds of formula (I) may be purified by the customary known methods, for example by crystallization, chromatography or extraction.
The enantiomers of the compounds of formula (I) may be obtained by resolution of the racemates for example by chromatography on a chiral column according to PIRCKLE W. H. et al., Asymmetric synthesis, Vol. 1, Academic Press (1983) or by formation of salts or by synthesis from chiral precursors. The diastereoisomers may be prepared according to known conventional methods (crystallization, chromatography or from chiral precursors).
The compounds of formula (I) may be optionally converted to addition salts with an inorganic or organic acid by the action of such an acid in an organic solvent such as an alcohol, a ketone, an ether or a chlorinated solvent. These salts also form part of the invention.
As examples of pharmaceutically acceptable salts, the following salts may be mentioned: benzenesulfonate, hydrobromide, hydrochloride, citrate, ethanesulfonate, fumarate, gluconate, iodate, isethionate, maleate, methanesulfonate, methylene-bis-∃-oxynaphthoate, nitrate, oxalate, pamoate, phosphate, salicylate, succinate, sulfate, tartrate, theophyllineacetate and p-toluenesulfonate.
The compounds of formula (I) exhibit advantageous pharmacological properties. These compounds possess a high affinity for the cannabinoid receptors and particularly those of the CB1 type. They are CB1-receptor antagonists and are therefore useful in the treatment and prevention of disorders affecting the central nervous system, the immune system, the cardiovascular or endocrine system, the respiratory system, the gastrointestinal apparatus and reproductive disorders (Hollister, Pharm. Rev.; 38, 1986, 1-20, Reny and Sinha, Prog. Drug Res., 36, 71-114 (1991), Consroe and Sandyk, in Marijuana/Cannabinoids, Neurobiology and Neurophysiology, 459, Murphy L. and Barthe A. Eds, CRC Press, 1992).
Accordingly, these compounds may be used for the treatment or prevention of psychoses including schizophrenia, anxiety disorders, depression, epilepsy, neurodegeneration, cerebellar and spinocerebellar disorders, cognitive disorders, cranial trauma, panic attacks, peripheral neuropathies, glaucomas, migraine, Parkinson""s disease, Alzheimer""s disease, Huntington""s chorea, Raynaud""s syndrome, tremor, obsessive-compulsive disorder, senile dementia, thymic disorders, Tourette""s syndrome, tardive dyskinesia, bipolar disorders, cancers, movement disorders induced by medicaments, dystonia, endotoxemic shocks, hemorrhagic shocks, hypotension, insomnia, immunological diseases, multiple sclerosis, vomiting, asthma, appetite disorders (bulimia, anorexia), obesity, memory disorders, in weaning from chronic treatments and alcohol or drug abuse (opioids, barbiturates, cannabis, cocaine, amphetamine, phencyclide, hallucinogens, benzodiazepines for example), as analgesics or potentiators of the analgesic activity of the narcotic and nonnarcotic drugs. They may also be used for the treatment or prevention of intestinal transit.
The affinity of the compounds of formula (I) for the cannabis receptors has been determined according to the method described by KUSTER J. E., STEVENSON J. I., WARD S. J., D""AMBRA T. E., HAYCOCK D. A. in J. Pharmacol. Exp. Ther., 264 1352-1363 (1993).
In this test, the IC50 of the compounds of formula (I) is less than or equal to 1000 nM.
Their antagonist activity has been shown by means of the model of hypothermia induced by an agonist of the cannabis receptors (CP-55940) in mice, according to the method described by Pertwee R. G. in Marijuana, Harvey D. J. eds, 84 Oxford IRL Press, 263-277 (1985).
In this test, the ED50 of the compounds of formula (I) is less than or equal to 50 mg/kg.
The compounds of formula (I) exhibit low toxicity. Their LD50 is greater than 40 mg/kg by the subcutaneous route in mice.
The following examples illustrate the invention.